Capacitive sense arrays may be used to replace mechanical buttons, knobs and other similar mechanical user interface controls. Touch sensing devices that utilize capacitive sense arrays are ubiquitous in today's industrial and consumer markets. They can be found on cellular phones, GPS devices, cameras, computer screens, MP3 players, digital tablets, and the like. Manufacture cost is the major concern of such touch sensing devices. There is a constant tradeoff between the function of the touch sensing devices and their costs. One of the major cost factors is number of Indium Tin Oxide (ITO) layers needed to assemble the capacitive sense elements to in the touch sensing devices. Both the cost and the function are proportional to the number of ITO layers. It would be ideal to support as many functions as possible on a single layer ITO stack-up. However, one major challenge of a single layer ITO application is accuracy. Accuracy in touch panel application is defined as error between the location of physical touch and the location sensed by the touch system. The sensed, or calculated location is based on the overall signal magnitude and profile. A single finger touch will generate signal across a neighborhood of sensor nodes which is called as signal profile. Signal degradation or deformed signal profile tends to cause accuracy problems in touch recognition.
FIG. 1 illustrates a conventional pattern design of a single ITO layer comprising capacitive sense array 100. The capacitive sense array 100 includes multiple rows 101 of sense elements such as each row 101 on the capacitive sense array 100 is covered by a pair of first set of sense elements 102 and a second set of sense elements 104 interleaved into each other's sub-fingers. A conductive object, such as a finger, lands on the capacitive sense array 100, and a signal is generated on both the first set of sense elements 102 and the second set of sense elements 104 along the same row. Since a finger would normally activate about three or more neighboring rows of sense elements, a signal profile can be readily obtained and a centroid can be generated with reasonable accuracy. However, the area between the rows 101 of the first set of sense elements 102 and the second set of sense elements 104 along vertical axis is known as a dead zone area as illustrated in FIG. 1. The dead zone as defined in the present application as an area between the pairs of the sense elements along the vertical axis that receives part of the signal from a sense element of one pair and part of the signal from a sense element of the other pair. However, this signal generated partly from each pair provides a split signal which is inconsistent and not sufficient for centroid determination. So, without a complete signal profile, the centroid determination of the finger would certainly have some error in the centroid algorithm as the data retrieved from the signal profile is unbalanced, resulting in an accuracy error periodically in between every row of the sense elements of the ITO layer of the touch panel device. A graphical representation of the above described periodic error is illustrated in FIG. 4. The periodic error 410 is substantially a sine wave that occurs along the y-axis for the row 101 of FIG. 1. The zero values on y-axis of the periodic error 410 indicate the signals generated at center of the sense element for the row 101. The values above and below the zero on y-axis represent the signals generated by the sense elements of the neighboring rows. These values represent the dead zone area